Inhibiting PHGDH with NCT-503 reroutes glucose-derived carbons into the TCA cycle, independently of its on-target effect

The small-molecule inhibitor of phosphoglycerate dehydrogenase, NCT-503, reduces incorporation of glucose-derived carbons into serine in vitro. Here we describe an off-target effect of NCT-503 in neuroblastoma cell lines expressing divergent phosphoglycerate dehydrogenase (PHGDH) levels and single-c...

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Bibliographic Details
Main Authors: Birte Arlt, Guido Mastrobuoni, Jasmin Wuenschel, Kathy Astrahantseff, Angelika Eggert, Stefan Kempa, Hedwig E. Deubzer
Format: Article
Language:English
Published: Taylor & Francis Group 2021-01-01
Series:Journal of Enzyme Inhibition and Medicinal Chemistry
Subjects:
Online Access:http://dx.doi.org/10.1080/14756366.2021.1935917
Description
Summary:The small-molecule inhibitor of phosphoglycerate dehydrogenase, NCT-503, reduces incorporation of glucose-derived carbons into serine in vitro. Here we describe an off-target effect of NCT-503 in neuroblastoma cell lines expressing divergent phosphoglycerate dehydrogenase (PHGDH) levels and single-cell clones with CRISPR-Cas9-directed PHGDH knockout or their respective wildtype controls. NCT-503 treatment strongly reduced synthesis of glucose-derived citrate in all cell models investigated compared to the inactive drug control and independent of PHGDH expression level. Incorporation of glucose-derived carbons entering the TCA cycle via pyruvate carboxylase was enhanced by NCT-503 treatment. The activity of citrate synthase was not altered by NCT-503 treatment. We also detected no change in the thermal stabilisation of citrate synthase in cellular thermal shift assays from NCT-503-treated cells. Thus, the direct cause of the observed off-target effect remains enigmatic. Our findings highlight off-target potential within a metabolic assessment of carbon usage in cells treated with the small-molecule inhibitor, NCT-503.
ISSN:1475-6366
1475-6374